JPH1019930A - Conductive contact - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive contact whose inductance and resistance can be lowered so as to cope with high frequencies. SOLUTION: Supporting holes 3a and 4a are provided for each of insulators 3 and 4 of the upper and lower side of multilayered insulators 2, 3 and 4 and support a pair of needle-shaped conductive bodies 5 and 6, which are prevented from coming out in protruding directions opposite to each other by the holes 3a and 4a, so as to protrude and recess freely. A conductive coil spring 7 integrally coupled with both needle-shaped conductive bodies 5 and 6 is contained in the middle hole 2a of the middle insulator 2 so as to blastedly energize each of needle-shaped conductive bodies 5 and 6 in each protruding direction. A coarsely-wound part 7b wound with a relatively more coarse pitch than a regularly-wound part 7a is provided for one part of the coil spring 7. Therefore, without increasing the number of winding, the margin of deflection is secured for the coarsely-wound part, and the lowering of inductance and resistance can be enhanced to cope with high frequencies.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive contact used for a contact probe for continuity inspection, which is particularly suitable for use in conducting an electrical test of a semiconductor device wafer or a bare chip cut from the wafer. is there.

[0002]

2. Description of the Related Art Conventionally, a conductive coil used for a contact probe for conducting an electrical inspection of a conductor pattern or an electronic element of a printed wiring board receives a compression coil spring in a holder coaxially. In some cases, a pair of conductive contacts are supported at both ends in the axial direction of the holder so as to be freely retractable, and both conductive needles are connected to both ends of the compression coil spring by soldering. Then, an electric signal input from one conductive needle is transmitted to the other conductive needle via a conductive compression coil spring.

However, when the electric signal flowing through the conductive contact is a high-frequency signal, a current flows through the coil-shaped conductor, which has an adverse effect. That is, when a high-frequency signal is passed through the coil-shaped conductor, the inductance increases and the resistance to the detection signal is obtained.

[0004]

In recent years, in a test of a semiconductor device in a wafer state, a test signal frequency has been increased, and a test signal having a frequency of several hundred MHz has been used. Therefore, it is required that the conductive contact applied to the test contact probe for transmitting such a high-frequency electric signal further promotes a reduction in inductance and resistance.

[0005]

SUMMARY OF THE INVENTION In order to solve such a problem and to realize a conductive contact capable of reducing the inductance and the resistance so as to cope with a high frequency, the present invention provides: A pair of conductive needles which are retained in the through-holes provided in the insulating support member in projecting directions opposite to each other and supported so as to be able to protrude and retract, respectively; A conductive coil spring that is received in the through hole and is integrally coupled with the conductive needle-like bodies so as to resiliently urge the spring. A coarse winding portion having a relatively coarse pitch was provided.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to specific examples shown in the accompanying drawings.

FIG. 1 is a schematic longitudinal sectional view showing an example of a conductive contact 1 of a movable double-ended type to which the present invention is applied. This conductive contact 1 is suitable for use in performing an electrical inspection by, for example, being attached to an inspection apparatus on the upper side in the drawing and being brought into contact with an object to be inspected arranged on the lower side,
Although only one conductive contact is shown in the figure, a plurality of conductive contacts are arranged in parallel according to the number of terminals. In the figure, the length in the radial direction is shown to be extremely long with respect to the length in the axial direction, but it is actually extremely elongated.

As shown in FIG. 1, the holder of the present conductive contact 1 has a relatively thick intermediate insulator 2 and an upper insulator 3 which is vertically stacked with the intermediate insulator 2 interposed therebetween. The lower insulator 4 is used. The intermediate insulator 2 is formed with an intermediate hole 2a penetrating in the thickness direction thereof. Each of the upper and lower insulators 3 and 4 has a support hole 3a slightly smaller in diameter than the intermediate hole 2a. 4a are formed so as to penetrate in the thickness direction, and the insulators 2 to 4 are laminated so that the intermediate hole 2a and the support holes 3a and 4a are coaxially aligned with each other, and are fastened by fastening means (not shown). Fixed. Each of the insulators 2, 3, 4 may be a synthetic resin material or a metal material. In the case of a metal material, the inner peripheral surface of the hole is coated with an insulating material.

The conductive contact 1 is of a movable type at both ends as described above, and the upper and lower conductive needles 5 and 6 are displaced in the axial direction by the upper and lower support holes 3a and 4a. It is freely supported. Each of the conductive needle-shaped members 5 and 6 has its protruding tip portion sharpened in the direction of protruding outward from each of the support holes 3a and 4a, and is expanded beyond each of the support holes 3a and 4a for retaining. It has enlarged portions 5a and 6a which are diametrically received and received in the intermediate hole 2a.

A conductive coil spring 7 interposed between the conductive needles 5 and 6 is coaxially received in the intermediate hole 2a, and both ends of the coil spring 7 are connected to the respective conductive needles. Each enlarged diameter portion 5a, 6a received in the intermediate hole 2a of the needle-like body 5, 6.
Pin-shaped coupling portions 5b projecting from each other
6b is connected by winding or soldering.

The conductive contact 1 thus constructed
Is used for a wafer test, for example, as shown in the figure, insulators 2, 3, and 4 as insulating support members are fixed to a substrate 8 on the inspection apparatus side in advance by screws or the like (not shown). The end of the internal circuit conductor 8a provided as a part of the circuit is exposed on the surface of the substrate 8 on which the insulator 3 is fixed (the lower surface in the figure).

By fixing the conductive contact 1 to the substrate 8 as described above, one of the conductive needles 5 resiliently strikes the exposed portion of the internal circuit conductor 8a. Are electrically connected (FIG. 1). Then, the other conductive needle-shaped body 6 is brought into contact with the work pad 9a of the work 9 to be tested, and the work 9 and the substrate 8 on the inspection apparatus side are electrically connected to perform a wafer test.

When the coil spring is used as a conductor,
The coefficient is A between the number of turns N and the inductance H.
Assuming that the spring length is L, there is a relationship of H = A · N ² / L, and it is important to reduce N as much as possible to reduce inductance. However, when used in a resilient manner, a certain amount of deflection is required, and about ten to several tens of turns are required.

The coil spring 7 according to the present invention is wound and formed so as to provide a steady winding portion 7a having a relatively fine pitch and a coarse winding portion 7b having a relatively coarse pitch with respect to the steady winding portion 7a. I have. Here, the spring constant of the coarsely wound portion 7b is larger than that of the steady wound portion 7a.

Therefore, when the conductive contact 1 is fixed to the substrate 8 as described above, one conductive needle 5 comes into contact with the internal circuit conductor 8a, and the stationary winding portion 7a first It sags and comes into close contact. Next, as shown in FIG. 2, when the conductive contact 1 is brought into a fixed state at a position close to the work 9 in order to bring the other conductive needle-shaped body 6 into contact with the work pad 9 a, the coarsely wound portion 7 b becomes To bend.

By doing so, for example, by making the coarsely wound portion 7b several turns, when the steady wound portion 7a is in close contact, only the coarsely wound portion 7b becomes a coil-shaped conductor portion, The inductance can be reduced as compared with the case where electricity is transmitted in a coil shape over the entire length of the spring portion. As the inductance H at that time, for example, in the case where the coarsely wound portion 7b is set to one turn, the result is obtained by substituting 1 into N in the above equation, so that the inductance can be extremely reduced. Furthermore, the number of turns can be reduced to one or less, and the inductance can be further reduced.

Further, by setting the deflection allowance of the coarsely wound portion 7b to such an extent that the amount of deflection against a difference in height due to a processing error of the work pad 9a as a contacted body can be absorbed, a substantial winding of the coil spring 7 can be achieved. The number can be minimized. For example, as described above, when setting is made such that a difference in height can be absorbed by one turn of the coarsely wound portion 7b, the work pads 9a and 9b are set as shown in FIG.
-Regarding the various height differences of 9c, each coil portion has one turn, and the inductance is only a difference of the spring length L, and the influence of the height difference is extremely small.

If the coarsely wound portion 7b, which is a coil portion having a higher resistance value, has approximately one turn, the resistance value is relatively lower than that of tens or tens of turns, and the conductive contact 1
The allowable current that can be supplied to the power supply can be increased, and a large current can be handled.

[0019]

As described above, according to the present invention, since the coarse coil portion is provided on the conductive coil spring that resiliently urges the conductive needle-shaped member, the bending allowance can be absorbed by the coarse coil portion. Thus, it is possible to secure a deflection allowance without increasing the number of windings, improve low inductance and low resistance, and cope with high frequencies.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view showing a conductive contact to which the present invention is applied.

FIG. 2 is a schematic longitudinal sectional view showing a state where a conductive contact is brought into contact with a work pad.

FIG. 3 is a schematic longitudinal sectional view showing a state of a conductive contact according to a difference in the amount of deflection.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conductive contact 2 Intermediate insulator 3 Upper insulator 4 Lower insulator 2a Intermediate hole 3a / 4a Support hole 5.6 Conductive needle-shaped body 5a / 6a Large diameter portion 7 Coil spring 7a Regular winding portion 7b Coarse winding Part 8 substrate 8a internal circuit conductor 9 work 9a, 9b, 9c work pad

Claims (1)

[Claims] 1. A pair of conductive needles which are retained in through holes provided in an insulating support member in projecting directions opposite to each other and supported so as to be able to protrude and retract, respectively, and each of said conductive needles A conductive coil spring that is received in the through hole and is integrally connected to the conductive needle-shaped bodies to resiliently urge the body in the projecting direction; A conductive contact comprising a coarsely wound portion having a relatively coarse pitch than other portions.